The Python idiom:

if __name__ == "__main__":
     ...

is most naturally written as:

(when (command-name)
   ...)

If we added a `command?` predicate, that would be:

(when (command?)
   ...)

However, it's probably better to use an explicit main procedure anyway.
IMHO that Python idiom is a hack.

I left `main` concerns out of this SRFI for now. Feel free to suggest
that they should be in scope.